Silver halide color photographic materials are imagewise exposed and then developed with an aromatic amine color developing agent to form a color image by the reaction of the resulting oxidation product of the developing agent with a color image forming coupler (hereinafter referred to as coupler). Usually, a combination of a yellow coupler, a cyan coupler and a magenta coupler is used in the color photographic materials.
Known magenta couplers include pyrazolone type, pyrazolobenzimidazole type, indazolone type and pyrazolcazole type couplers including pyrazolotriazole. Four equivalent couplers are known which theoretically require 4 mol of silver halide to form one mol of a dye and two equivalent couplers are known which theoretically require 2 mol of silver halide to form one mol of a dye.
These couplers form a colored stain which is a phenomenon wherein the unexposed area is colored during the passage of time after development, irrespective of the types of couplers used. However, the difference in the degree of the colored stain varies depending upon the developing methods, the compositions of the developing solutions and the difference in the deterioration of the developing solutions. The two equivalent couplers are more liable to form the colored stain.
Stain in the unexposed area of the silver halide color photographic material has an influence on the quality of the white portion of an image. Further, stain has effects on the color muddiness and deteriorates visual sharpness. Particularly, when reflecting materials (e.g., color paper, reversal color paper) are used, the reflection density of the stain is theoretically enhanced to several times the transmission density so that the image is deteriorated even by a slight amount of stain. Hence, stain is an important factor in the quality of photographic products.
Stain in the unexposed area after development can hardly be inhibited even by the use of anti-fading agents such as hydroquinones, hindered phenols, tocopherol, chroman, coumaran, etc., unlike the type of yellow stain which is formed by the decomposition of the couplers themselves by light or heat.
U.S. Pat. No. 4,483,918 proposes a method wherein two equivalent 5-pyrazolone magenta couplers are used in combination with aniline compounds for the purpose of preventing colored stain from being formed. Further, the present inventors have previously proposed the use of compounds which are reacted with developing agents remaining in the processed photographic materials after development or with oxidized products capable of coupling with coupler to form a dye, whereby there can be formed substantially colorless compounds (see, European Patent Laid-Open Nos. 255,722, 258,662, 228,655 and 230,048 and U.S. Pat. No. 4,704,350). Particularly, magenta colored stain is remarkably visual even when a trace amount of stain is formed. When the recording and storage of the photographic materials are taken into consideration, it is extremely important to prevent a colored stain from being formed as well as to preserve the image from deterioration by light, heat and moisture over a long period of time. The previously proposed inhibitors are not always sufficient to acheive this goal.
Further, the above-described aniline compounds do not have a sufficient effect on two equivalent magenta couplers which have been newly developed. Thus, there is a demand for the development of an alternative method to reduce stain.
Furthermore, a short time for development (i.e., rapid processing, benzyl alcohol-free development, and processing requiring no or little rinsing water) has been recently demanded to meet the requirements of customers or to maintain the natural environment. It is necessary to guarantee the preservability of the color image and a sufficient color density even when the processing is carried out by using processing solutions whose composition ratio is greatly changed during operation.